Door latch mechanism



Aug. 21, 1956 F. KAISER 2,759,751 DOOR LATCH MECHANISM Filed Feb. 8, 1955 2 Sheets-Sheet l /5 b" 1. i l a 0 1 .5

mmvroze. fleagz'sez;

United States Patent Ofitice 2,759,75l Patented Aug. 21, 1956 2,759,751 DOOR LATCH MECHANISM Fred Kaiser, Brooklyn, N. Y. Application February 8, 1955, Serial No. 486,881 5 Claims. (Cl. 292-337) Another object of the invention is to provide means of novel form and location for both securing together the casing side sections in assembled relation and for additional purposes, said means including a hollow rivet so located as to receive extension therethrough of one of a pair of knob rose bushing sleeves, whereby to determine the proper position of the latch mechanism in the mortise of a door to be served thereby, and at the same time to assure proper alignment of the latch retracting cam cylinder of the latch mechanism for reception of a door knob spindle; said hollow rivet being additionally adapted to serve as a back stop for the compression spring which yielda-bly holds in normal initial position, the latch retractor frame of the latch mechanism; said casing :side

sections having means, inwardly struck from the side walls thereof, which retains said compression spring against shifting displacement from its back stopped relation to said hollow rivet.

A further object of the invention is to provide the rear end of the latch mechanism casing with an externally projecting fork element to engage the other of said pair of knob rose bushing sleeves, together with rivet means adapted to both secure said fork element in assembled relation to the casing and to further secure together 'the casing side sections in their operative assembled relation.

The above and other objects will be understood from a reading of the following description of this invention in connection with the'accompanying drawings, in which:

Fig. 1 is a horizontal plan view of the knob actuated mortised door latch mechanism as operatively mounted in a door to be served thereby, the door being shown in section. i

Fig. 2 is a vertical longitudinal section, taken on line 22 in Fig. l; and Fig. 3 is a longitudinal horizontal section, taken on line 3-3 in Fig. 2.

Fig. 4 is a vertical cross-sectional view, taken on line 44 in Fig. 2; Fig. 5 is a vertical cross-sectional view, taken on line 5-5 in Fig. 2; and Fig. 6 is a vertical crosssectional view, taken on line 6-6 in Fig 2; these views being drawn on an enlarged scale.

Referring to the drawings, in which like characters of reference are employed to indicate corresponding parts,

the reference character 10 indicates a door to ,whichthe,

latch mechanism of this invention is applied. Mounted in a mortised opening, which extends into the door body from its free edge, is thecasing in which the latch mechanism is housed. This casing is longitudinally divided in vertical plane so as to comprise identical complementary side sections 11 and 12, which are preferably formed by sheet metal stampings, the open inner sides of which are opposed one to the other. The casing thus formed is open at its outer end. The top and bottom walls of each casing side section, at the junctures thereof with their side walls, are indented to provide longitudinal slideway members 13, which extend from points rearwardly spaced from the outer open end of the casing to the rear end of said casing. Forwardly offset adjacent to their rear ends, the side walls of the casing side sections 11 and 12 are provided with transversely aligned openings bounded by inwardly projecting annular bearing flanges 14, by which a rotatable knob spindle engageable cam cylinder, hereinafter described, is supported. The casing side sections 11 and 12 are secured together in casing forming re lation, at a point intermediate said cam cylinder bearings and the outer end of the casing, by a transverse hollow rivet 15, which is outwardly spaced from the axis of said cam cylinder bearings at a distance corresponding to the spacing of knob rose bushing sleeves relative to the axis of a knob spindle by which the latch mechanism is to be actuated; and the bore 16 of said hollow rivet 15 corresponds in diameter to the external diameter of a knob rose bushing sleeve. The side walls of the casing side sections 11 and 12 are formed to provide countersunk seats 17 for the reception of the riveted over end portions 18 of the hollow rivet 15.

Projecting exteriorly from the rearward end of the casing is a fork element 19, the same being disposed to lie in the medial vertical plane of said casing, and between and so that its side faces are abutted by inwardly projecting angular end flanges 20 with which the rear ends of the casing side sections are respectively provided. The fork element 19 is secured in assembled relation to the casing by a transverse anchor post 21 which extends therethrough, and which includes a diametrically enlarged spacer portion 22 disposed between said fork element and one of the casing side sections. Said anchor post terminates at its opposite ends in rivet studs 23, which project through the respective casing side sections 11 and 12, with their external ends riveted over to form fastening heads 24. By this arrangement, not only is the fork element secured in place, but the casing side sections are additionally secured in casing forming relation. The outwardly 1 open notch 25 of the fork element is adapted to straddle q of the retractor frame is easy,

a knob rose bushing sleeve.

The latch mechanism, which is housed in the above described casing, comprises a latch member 26 that slidably engages in the outer open end portion of the casing, so as to normally project outwardly therefrom to its operative door latching position. Extending axially rearward from the latch member 26, as a unitary part thereof, is a stem 27. Journaled by its end hub portions 28, so as to be rotatively supported between the casing side sections 11 and 12, is a knob spindle engageable cam cylinder 29 having oppositely and perpendicularly projecting cam arms 30 in offset connection with its forward side. Disposed intermediate thecam cylinder 29 and the latch member 26 is a longitudinally movable U-shaped latch I retractor frame 31, only the marginal portions of the legs 32 of which are slidably supported by and between slide- Way members 13 of the casing, whereby said legs can straddle both the hollow rivet 15 and the cam cylinder 13 are contacted only tractor frame legs, frictional resistance to sliding movement of the retractor frame relative to the casing is reduced to a minimum. As a result of this, knob actuation or what may be termed soft, so that resistance to hand turning of the knob is greatly diminished, and hard turning action thereof is avoided. Each leg 32 of the retractor frame is provided with an open slot 33 through which the free and portions of the cam arms 30 of the cam cylinder project so as to engage angular abutments 34 at the rearward ends of said slots. Preferably, the top and bottom walls of the casing are formed with suitably located openings or slots 35 to provide clearance ways to accommodate said abutments 34 as moved relative to the casing by longitudinal movements of the retractor frame. The forward end of the retractor frame is pierced by an opening 36 through which the stem 27 of the latch member 26 extends. The end of said stem 27 is provided with an enlargement or coupler head 37 behind and so as to be engaged by said forward end of the retractor frame, whereby rearward movement imparted to said retractor frame withdraws the latch member 26 into the casing interior from normal outward projection therefrom. A compression spring 38 is disposed to extend between the hollow rivet 15, by which it is backed, and the forward end of the retractor frame 31. This compression spring yieldably thrusts the retractor frame forward to its normal latch member releasing position, while at the same time holding the abutments 34 thereof engaged bythe cam arms 39 of the cam cylinder 29. Struck out from the side walls of each casing side section 11 and 12, adjacent the hollow rivet 15, are inwardly projecting spaced apart, divergent tongues 39. These tongues embrace the end portion of the compression spring 38 which abuts the hollow rivet 15, whereby to retain said spring against shifting displacement from its back stopped relation to said hollow rivet, and from axially parallel relation to and between the retractor frame legs 32. A compression spring 40. around the stem 27, intermediate the latch member 26 and the forward end of the retractor frame 31 yieldably forces the latch member 26 to its projected door latching position relative to said retractor frame.

The means for operating the door latch mechanism comprises door knobs 41, respectively mounted upon opposite sides of the door 10. The shanks of said knobs are journaled in rose plates. 42. Extending between the door knobs is a knob actuatable spindle 43, preferably of polygonal cross-section shape. through a correspondingly shaped. axial opening 44 with which the cam cylinder 29 is provided, whereby said cam cylinder can be rotated by turning of either door knob, so as to cause the cam arms 30 to pullback the retractor frame 31, and thus withdraw the latch member 26. from its door latching position. The rose plates. are afiixed in place, respectively on opposite faces. of the door 10, by tying means extending therebetween and transversely through the door body, and. through. the latch mechanism mortised. into the latter. The tying means comprises. a pair of internally screwthreaded bushing sleeves 45 which are aflixed to one knob rose plate; for extension. therefrom, and fastening screws 46 which; extend; from the rose plate of the opposite knob to screw into; said bushing sleeves 45. Said bushing sleeves are respectively outwardly spaced at predetermined distance from opposite sides of the axis of the knob and; spindle assembly. One said bushing sleeve extends through the bore of the hol.- low rivet by which the casing side sections. 11. and: 12 are joined in casing forming relation. Since said hollow rivet 15 is spaced from the axis of. the cam cylinder 29- at a distance corresponding to the distance that a. bushing sleeve is spaced from the axis of the knob and spindle as.- sembly, extension of an outer bushing sleeve through the hollow rivet assures both proper position of the. latch mechanism within the mortise of the door and, proper alignment of the latch retracting cam cylinder 29: for reception of the knob actuatable spindle 43. Theother or inner bushing sleeve extends through. the notch of the rearwardly projecting fork element 19. of the. latch, casing.

From the above it will now be apparent that the provision and location of the hollow rivet 15, by which the Said spindle 43. passes casing side sections 11 and 12 are joined in casing forming relation, affords a novel structural feature having the following advantages:

(1) The hollow rivet 15 serves to secure the casing side sections 11 and 12 together.

(2) Said hollow rivet 15 being located intermediate the cam cylinder 29 and the outer open end of the casing from which the latch member 26 projects, and in predetermined spaced relation to these parts, said hollow rivet receives extension therethrough of a rose plate bushing sleeve 45, thus serving as a guide for properly positioning the latch mechanism in the door mortise, and so that the cam cylinder 29- is properly aligned to receive extension therethrough of the knob actuatable spindle 43 by which it is to be operated.

(3) Said hollow rivet 15, by reason of its location forwardly of the cam cylinder 29, being also adapted to serve as a back stop for the retractor frame compression spring 38.

Another novel feature of the casing construction comprised the provision of the divergent tongues 39 which are struck inwardly from the side walls of the casing side sections 11 and 12, so as to be disposed adjacent to the 'hollow rivet 15 to oppose opposite sides of the compression spring 38, thus serving to embrace the abutting end of the latter so as to retain the same against shifting displacement from its back stopped relation to said hollow rivet.

The casing construction involves additional novelty with respect to the fork element 19 and the means by which it is attached to and for projection from the rearwardend of the casing.

Having now described my invention, I claim:

1. In a mortised door latch mechanism, a casing formed by opposed identical complementary side sections having side, bottom and top walls and having an open outer end, a latch member slidably supported by said open outer end of the casing for projection therefrom, a latch member retractor frame longitudinally movable within said casing, the junctures of side, bottom and top walls of each casing side section beingindented to provide inwardly ofiset ledges forming retractor frame slideways extending longitudinally from points rearwardly spaced from the open outer end of the casing to the rear end thereof, said slideways being engagea-bl'e only by the longitudinal marginal portions of said retractor frame, whereby frictional resistance to retractor frame movement is substantially reduced, a retractor frame actuating cam cylinderrotatably journaled in and between the casing side walls at a point forwardly spaced from the casing rear end, a transverse hollow rivet to secure said casing side sections together, said hollow rivet being disposed intermediate the cam cylinder and the outer end of the casing in predetermined spaced relation to the former, whereby extension of a forward bushing sleeve of a door knob assembly through the bore of said hollow rivet accurately determines the operative position of the casing and latch member in a door mortise and at the same time aligns the cam cylinder for axial extension therethrough of the spindle of said door knob assembly, and a compression spring cooperative with said retractor frame to yieldably hold the same in normal relation to the cam cylinder for actuation thereby, said hollow rivet serving as: a back stop for said compression spring.

2. In a.- mortised door latch mechanism as defined by claim 1, wherein the casing side walls each further includevertically spaced; tongues struck therefrom to project into the casing interior adjacent to the forward side of saidhollow rivet, said tongues being adapted to embrace said compression spring. whereby to retain the same against displacement from axially parallel relation to the retractor frameand from back stopped relation to saidhollow rivet.

3. In a mortiseddoor latch mechanism as defined by claim 2, wherein the. casing further includes a fork element aflixed, thereto for. projection from the rear end thereof in an axially aligned perpendicular plane, and so as to straddle a rearward bushing sleeve of the door knob assembly when the door latch mechanism is operatively disposed Within a door mortise.

4. In a mortised door latch mechanism, a casing formed by opposed identical complementary side sections having side, bottom and top walls and having an open outer end, a latch member slidably supported by said open outer end of the casing for projection therefrom, a spring biased latch member retractor frame longitudinally movable Within the casing, the junctures of said side, bottom and top walls of each casing side section being indented to provide inwardly oflfset ledges forming retractor frame slideways extending longitudinally from points rearwardly spaced from the open outer end of the casing to the rear end thereof, said slideways being engageable only by the longitudinal marginal portions of the retractor frame, whereby frictional resistance to retractor frame movement is substantially reduced, and a retractor frame actuating cam cylinder rotatably journaled in and between the casing side walls at a point forwardly spaced from the casing rear end.

5. In a mortised door latch mechanism, a casing formed by opposed identical complementary side sections having side, bottom and top Walls and having an open outer end, a latch member slidably supported by said open outer end of the casing for projection therefrom, a latch member retractor frame longitudinally movable within the casing, a retractor frame actuating cam cylinder rotatably journaled in and between the casing side walls at a point forwardly spaced from the casing rear end, a transverse hollow rivet to secure said casing side sections together, said hollow rivet being disposed intermediate the cam cylinder and the outer end of the casing in predetermined spaced relation to the former, whereby extension of a forward bushing sleeve of a door knob assembly through the bore of said hollow rivet accurately determines the operative position of the casing and latch member in a door mortise and at the same time aligns the cam cylinder for axial extension therethrough of the spindle of the door knob assembly, and a compression spring cooperative with said retractor frame to yieldably hold the same in normal relation to the cam cylinder for actuation thereby, said hollow rivet serving as the back stop for said compression spring.

References Cited in the file of this patent UNITED STATES PATENTS 2,268,974 Voight Jan. 6, 1942 2,503,192 Cerf Apr. 4, 1950 2,634,151 Russell et al. Apr. 7, 1953 

